California study found certain areas have high numbers of parents who forgo immunizing kids
WebMD News from HealthDay
By Steven Reinberg
HealthDay Reporter
MONDAY, Jan. 19, 2015 (HealthDay News) -- Parents who refuse to have their children vaccinated appear to be clustered in certain areas, a new study suggests.
Among more than 150,000 children in 13 counties in Northern California, the researchers found five clusters where kids had missed one or more vaccinations by the time they were 3 years old.
"It's known from other studies that areas where there are clusters of vaccine refusal are at higher risk of epidemics, such as whooping cough epidemics," said lead investigator Dr. Tracy Lieu, a pediatrician and director of the division of research at Kaiser Permanente Northern California, in Oakland.
"Clusters may deserve special outreach efforts to make sure parents have all the information they need to make informed decisions about vaccination," she said.
Specifically, the researchers found the rate of missed vaccinations within these clusters ranged from 18 percent to 23 percent, compared with a rate of missed vaccinations outside the clusters of 11 percent.
Missed vaccinations for measles, mumps, rubella and varicella (chickenpox) were similar in all the clusters, they added.
In addition to missed vaccinations, children whose parents refused vaccinations were also found in clusters. In the clusters, vaccine refusal rates ranged from 5.5 percent to 13.5 percent, compared with 2.6 percent outside the clusters, Lieu's team found.
Parents who decline or delay vaccines do so for a variety of reasons, Lieu explained.
"Many parents have questions about the safety of vaccines, and it's natural to have these concerns even though there's reassuring evidence available about many questions regarding vaccine safety," she said.
"Sometimes parents decline vaccines they don't think are necessary; other studies have found this tends to happen with chickenpox vaccine, for example. Other times parents are concerned that vaccines might cause side effects," Lieu added.
The report was published online Jan. 19 and in the February print issue of the journal Pediatrics.
Dr. Paul Offit, a professor of pediatrics at Children's Hospital of Philadelphia, said there are two possible reasons people don't have their children vaccinated: they choose not to; they don't have good access to medical care.
source : Vaccine Opponents Often Cluster in Communities
